The invention relates generally to liquid filtration devices. More particularly, the invention relates to a locking liquid filter assembly that prevents an unauthorized user from removing the filter media cartridge.
Commercial vending machines for dispensing liquids such as coffee or soft drinks typically filter the water they use before they are dispensed by passing the supply water through an appropriate filter. Filtering devices are also commonplace in water coolers, ice makers, and consumer appliances such as refrigerators for filtering drinking water and for ice production. Commercial and domestic filtering devices of this type have a limited useful life and require frequent replacement.
The replaceable filters employed in these types of filter assemblies are manufactured in accordance with particular design use specifications and performance parameters provided by the filter manufacturer. In many cases, the filter media used in such filters consists of a proprietary material or is manufactured using a proprietary process. Therefore, the filter manufacturers often recommend that replacement cartridges be purchased from the original equipment provider so as to ensure the integrity and proper operation of the filtering system.
The filter media cartridge used in typical filter assemblies is configured as either a one-piece filter cartridge that contains the filter media in a water-tight shell or a separate filter media element that slides into a water-tight cover. The filter media cartridge is coupled to a filter assembly head which directs a liquid from a supply to flow through the filter media cartridge and out to a destination for use.
However, the ease at which the filter media cartridge may be removed or replaced from a filter assembly creates a situation where tampering may just as easily take place. For filter assemblies that are not enclosed in a secured enclosure, or are exposed due to piping considerations, the filter assemblies may be tampered with. One scenario is where a hooligan removes the filter media cartridge from a filter assembly and causes a flooding situation. Another may be where the filter media cartridge is removed from a filter assembly, contaminated, and then replaced.
To ensure that the correct filter media cartridge is always used in a particular filter assembly installation and to prevent unauthorized removal, a secure filter assembly is desired.